1. Field of the Invention
The invention generally relates to computer database systems. More particularly, the invention relates to techniques for processing query conditions having filtered fields within a data abstraction environment.
2. Description of the Related Art
Databases are well known systems for storing, searching, and retrieving information stored in a computer. The most prevalent type of database used today is the relational database, which stores data using a set of tables that may be reorganized and accessed in a number of different ways. Users access information in relational databases using a relational database management system (DBMS). Queries of a relational database may specify which data items should be retrieved, how to join various data items, and conditions (predicates) that must be satisfied for a particular data item to be included in a query result table.
The complexity of constructing a query statement, however, generally makes it difficult for average users to compose queries of a relational database. Because of this complexity, users often turn to database query applications to assist them in composing queries of a database. One technique for managing the complexity of a relational database, and the SQL query language, is to use a database abstraction model. Generally, a database abstraction model is constructed from logical fields that map to data stored in the underlying physical database.